Re: [libvirt] [PATCH v5 10/13] qemu: Generate and use zPCI device in QEMU command line

17 Sep 2018


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On Tue, 2018-09-04 at 16:39 +0800, Yi Min Zhao wrote:
[...]
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+char *
+qemuBuildZPCIDevStr(virDomainDeviceInfoPtr dev)
+{
+    virBuffer buf = VIR_BUFFER_INITIALIZER;
+
+    virBufferAddLit(&buf, "zpci");
+    virBufferAsprintf(&buf, ",uid=%u", dev->addr.pci.zpci.uid);
+    virBufferAsprintf(&buf, ",fid=%u", dev->addr.pci.zpci.fid);
+    virBufferAsprintf(&buf, ",target=%s", dev->alias);
+    virBufferAsprintf(&buf, ",id=zpci%u", dev->addr.pci.zpci.uid);
All of the above can be a single virBufferAsprintf() call.
Sure.
[...]
+static int
+qemuAppendZPCIDevStr(virCommandPtr cmd,
+                     virDomainDeviceInfoPtr dev)
I'd call this qemuCommandAddZPCIDevice() or something like that.
OK.
...
+{
+    char *devstr = NULL;
+
+    virCommandAddArg(cmd, "-device");
Empty line here.
Yeah.
...
+    if (!(devstr = qemuBuildZPCIDevStr(dev)))
+        return -1;
[...]
+static int
+qemuBuildExtensionCommandLine(virCommandPtr cmd,
+                              virDomainDeviceInfoPtr dev)
Same comment about the naming as above.
OK.
...
+{
+    if (!virZPCIDeviceAddressIsEmpty(&dev->addr.pci.zpci))
+        return qemuAppendZPCIDevStr(cmd, dev);
+
+    return 0;
I'd rather see this as
if (virZPCIDeviceAddressIsEmpty(&dev->addr.pci.zpci))
       return 0;
return qemuAppendZPCIDevStr(cmd, dev);
instead.
How about using switch? I think extension flag should be check and
在 2018/9/11 下午10:31, Andrea Bolognani 写道:
then build command for each case although there's only zpci case.
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[...]
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@@ -4327,6 +4390,9 @@ qemuBuildSoundCommandLine(virCommandPtr cmd,
          if (sound->model == VIR_DOMAIN_SOUND_MODEL_PCSPK) {
              virCommandAddArgList(cmd, "-soundhw", "pcspk", NULL);
          } else {
+            if (qemuBuildExtensionCommandLine(cmd, &sound->info) < 0)
+                return -1;
Do the codecs (handled immediately below) require a zpci device
as well? I figure they don't, but I also don't know much about
sound devices :)
If its address is PCI, we should add a zpci for it. zPCI is not related 
to its functionality.
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[...]
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@@ -9086,6 +9171,9 @@ qemuBuildShmemCommandLine(virLogManagerPtr logManager,
switch ((virDomainShmemModel)shmem->model) {
      case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM:
+        if (qemuBuildExtensionCommandLine(cmd, &shmem->info) < 0)
+            return -1;
+
          devstr = qemuBuildShmemDevLegacyStr(def, shmem, qemuCaps);
          break;
@@ -9104,6 +9192,9 @@ qemuBuildShmemCommandLine(virLogManagerPtr logManager,
ATTRIBUTE_FALLTHROUGH;
      case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_DOORBELL:
+        if (qemuBuildExtensionCommandLine(cmd, &shmem->info) < 0)
+            return -1;
+
          devstr = qemuBuildShmemDevStr(def, shmem, qemuCaps);
          break;
This looks wrong: you should call qemuBuildExtensionCommandLine()
later on, like
if (!devstr)
       return -1;
if (qemuBuildExtensionCommandLine(cmd, &shmem->info) < 0)
     return -1;
virCommandAddArgList(cmd, "-device", devstr, NULL);
instead.
Good catch. Thanks for your comments.

-- 
Yi Min

    